[SOLVED] PIC 16F628A unsupported part

I have a pickit 2 clone running pickit 2 v 2.61.
I have two pic 16f628a . when i try to program the software says unsupported part ID 3fe0
I have several other chips that are working correctly. I am connecting them in zif socket checking on the operation manual and also connected on breadboard.

What to do ?????

The part ID for the 16F628A is 1060 but the IDMASK is 3fe0 so it seems you are not reading that address and reading all '1' bits through the mask instead.

Is it possible to read back from a previously programmed 16F628a to see if it reads all ones at every address?

Brian.

yes tried with a per-programmed pic . same as before reads it as 3fe0

Hi,
I also had some strange issues with PIC16F628A about a year ago.
Are you using a stable power supply, decoupling capacitor 100nF between +5 and ground ?

If you are using a breadboard keep the wires short like 10 cm.

Sorry, I should have been more specific. When you read back the pre-programmed PIC, is the program data correct? I'm trying to establish whether the whole PIC is giving wrong data or just the ID location.

As nilses found out, if the serial data in the programming command is corrupted it will return wrong information.

Brian.

Hi,

I almost gave up using PIC about a year ago. I got a tip from a friend here who recommended PIC18F1320. Success at once.
I'm not sure but I assume I had some bad breadboards,cables etc.

Good luck

Nils

it only reads unsupported part

The big clue is in the yellow box in the middle "No device detected" which means just that. The error isn't that it read back the wrong device ID, it's that it didn't read anything back at all!

The reason it shows 3FE0 is because that's the standard bit mask for device IDs. In binary it is 0011 1111 1110 0000, when you consider the leftmost two bits are always zero and the silicon revision is stored inthe right most 5 bits, it leaves the middle '1' bits as the device type identifier. The mask is ANDed with the bytes read from the PIC so it only sees the ID and not the silicon revision. In your case it effectively read nothing and the result was 1111 1111 1111 1111 which ANDed with the mask results in 3FE0.

Your real problem is either in the wiring between the Pickit2 and the PIC or, if it not a real Microchip one but a clone, the power rails are inadequate. If you are trying to program it while the PIC is connected to another circuit, check it meets the requirements as specified in the Pickit2 manual.

I have several Pickit2 programmers and they work hard programming hundreds of PICs, including 16F628A and I have never had a single failure.

Brian.

Thank you all for your help , I really appreciate it. Bought a new pic 16f628a and it works fine.